The objective of the project is to design a new distributed actuation system along the needle’s body (active/smart needling), exploiting the steering advantage of the bevel-tip geometry (bevel angle), developing a flexible needle body having sensors at the needle tip and along the body for real-time tracking/detection of the needle using a feedback closed-loop control for real-time steering of the needle toward the target. We present two types of needle design and actuation techniques: Longitudinal Body Segment (LoBS) design, and Lateral Body Segment (LaBS) design. For LoBS design, the needle is separated into multiple segments along its length to improve maneuverability of the needle tip. This device incorporates four Nitinol wires per segment about its tubular substructure. The ends of each wire are secured to steel anchors, which are attached to non-conducting collets. The displacement and the speed of actuation is a function of the power supplied to each Nitinol wire. The amount of power is controlled using Pulse Width Modulation. Bending in arbitrary directions can be accomplished by adjusting the electrical duty cycles of the Nitinol wires. For LaBS design, the needle body is made of Nitinol having lateral segments (two or multiple of paired segments along the needle length). Each segment is an actuator made of Nitinol, which will be capable of manipulating the needle tip according to the sensory feedback information. The distal end of the actuator segments of the needle body are hinged at different points when the needle needs to be curved down the needle body segment can be actuated so that force which will produce moment about the opposite point. Therefore, by manipulating the force the amount of needle curvature can be controlled. By rotating the needle at desired angle, any needle trajectory can be achieved for reaching the target while avoiding obstacles (or critical organ) and conforming organ geometry.

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